Stockholm Awareness System
Overview
The SAS activity is focused on the development of a prototype command
and control system that uses a 3D city model as a means of supporting situation
awareness of remote activities. The system 
presents users
(operators) with a view from a 3D model of Stockholm in which remote units
(e.g., personnel and vehicles) have virtual representations, indicating their
physical position and to some extent activity. These representations are
updated continuously as a result of the activities of the physical units
(e.g., via the use of GPS), thus providing the operators with an up-to-date
view of the state of the remote work force. For instance, in a fire fighting
scenario, the system will display the positions of individual fire fighters
and vehicles, which helps operators to determine if more resources needs
to be directed to the scene of the fire, etc. Operators are able to navigate
the 3D model in order to locate the units and assess the situation. Hoovering
above the city at a high altitude might allow for an overview understanding
of what's going on, while zooming in close to the scene will give a more
detailed view of the position and activity of individual units.
Mobile devices
The project is investigating ways to allow personnel working in the city
to access the virtual city model using a mobile device (PDA, telephone, etc.).
This will give individual workers the same overview as control room operators,
and allows the 3D city model to be used as the basis for information exchange
between all the system users (workers and control room operators alike).
Remote users can point at or interact with objects in the 3D model as a complement
to verbal conversation. For instance, the system currently allows operators
to drag a document (e.g., MS Word) from the desktop onto the 3D window,
thus creating a graphical object representing the document inside the 3D
model. The object is visible to all remote users via their PDAs and by clicking
on it they can access the document which it represents. An operator can thus
place documents in the form of 3D objects on specific positions inside the
3D model where they can be accessed by all users of the system. It is also
possible to send documents directly to specific users (without having to
create a 3D object), for instance to give orders, send information such as
maps, drawings of buildings, etc.
Industrial relevance
The work is done in collaboration with AerotechTelub AB. The company has
an interest in using distributed, multi-user 3D systems as the basis for
simulators and command and control applications for the military as well
as civilian markets (e.g., search an rescue, fire fighting, etc.). AerotechTelub
AB are currently developing a detailed 3D model of some of the central areas
of Stockholm city, which are used as the basis for the demonstrator developed
within this activity. The resulting software framework and demonstrator will
be transferred to AerotechTelub AB, to be used to prototype, develop and
demonstrate future products. The command-and-control system has been
demonstrated by AerotechTelub on the Nordic Road & Traffic fair in Älvsjö
in september 2002.
Much effort has been spent on integrating a positioning system consisting
of a GPS receiver combined with a dead reckoning (DR) module (see image).
The idea is that if the GPS signal is lost, the DR module will take over
and continue to provide a lat/long position based on the user's current heading
and stride length information. The system is owned by FMV and has been made
available to the project by AerotechTelub. The work have consisted of interfacing
the positioning system to a IPAQ PDA and converting the GPS data to coordinates
in the Stockholm 3D model. Tests in which a person has been moving around
inside the Stocholm city center have been performed on several occasions.